Document Type


Publication Title

Geophysical Research Letters

Publication Date


Issue Number


Publication Number


Volume Number


Abstract/ Summary

Interior ice elevations of the West Antarctic Ice Sheet (WAIS) during the last glaciation, which can serve as benchmarks for ice-sheet models, are largely unconstrained. Here we report past ice elevation data from the Ohio Range, located near the WAIS divide and the onset region of the Mercer Ice Stream. Cosmogenic exposure ages of glacial erratics that record a WAIS highstand similar to 125 m above the present surface date to similar to 11.5 ka. The deglacial chronology prohibits an interior WAIS contribution to meltwater pulse 1A. Our observational data of ice elevation changes compare well with predictions of a thermomechanical ice-sheet model that incorporates very low basal shear stress downstream of the present day grounding line. We conclude that ice streams in the Ross Sea Embayment had thin, low-slope profiles during the last glaciation and interior WAIS ice elevations during this period were several hundred meters lower than previous reconstructions.

Citation/Publisher Attribution

Ackert, RP, Mukhopadhyay, S, Parizek, BR, and Borns, HW, 2007, Ice Elevation Near the West Antarctic Ice Sheet Divide During the Last Glaciation: Geophysical Research Letters, v. 34, L21506. To view the published open abstract, go to and enter the DOI.

Publisher Statement

© Copyright 2007 American Geophysical Union




publisher's version of the published document